The present disclosure relates to a power receiving unit receiving power from a power feeding unit wirelessly (in a non-contact manner), a power receiving control method used in such a power receiving unit, and a non-contact feed system and an electronic apparatus that each use such a power receiving unit.
In recent years, a feed system performing wireless power feeding (also called wireless power transfer, contact free, or non-contact power feeding) on consumer electronics devices (CE devices) such as mobile phones and portable music players has attracted attention. In such a feed system, for example, an electronic apparatus (such as a mobile phone) having a power receiving unit may be charged when the electronic apparatus is placed on a power feeding unit such as a power feeding tray. In other words, in such a feed system, the power feeding is allowed to be performed without connecting the power feeding unit and the power receiving unit by a cable or the like.
Examples of the method of performing such wireless power feeding may include, for example, an electromagnetic induction method and a magnetic field resonance method (also called magnetic resonance method) using resonance phenomenon. In these methods, power is transmitted with use of magnetic coupling between a power feeding coil of a power feeding unit and a power receiving coil of a power receiving unit. Among them, as compared with the electromagnetic induction method, advantageously, the magnetic field resonance method is allowed to transmit power even if the power feeding unit and the power receiving unit are away from each other, and feeding efficiency in the magnetic field resonance method does not particularly drop even if positioning between the power feeding unit and the power receiving unit is insufficient.